Pneumatic action for player-pianos.



UNITED STATES PATENT OFFICE.

EMORY o. I-IISCOCK, or CHICAGO, ILLINOIS, ASSIGNOR r0 w. 'w. KIMB'ALL COMPANY, or CHICAGO, ILLINOIS, A CORPORATION or ILLINOIS.

PNEUMATIC ACTION FOR PLAYER-PIANOS.

Specification of Letters Patent.

Patented J uiy 27, 1915.

Original application filed December 30, 1912, Serial No. 739,227. Divided and this application filed June 2, 1913. Serial No. 771,366.

To all whom it may concern Be it known that I, EMORY C. IIIscooK, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Pneumatic Actions for PlayeiPianos, of which the following is a specification.

This invention relates to the art of player pianos, and has reference more particularly to the improvements in the pneumatic actions employed in such instruments.

Among the various objects attained by the invention are, the provision of an improved construction of molded valve-chest and upper stationary pneumatic section based on a divided unit system, that is, a system in which said parts are made in two separable structures instead of a single unitary system, affording increased eiiiciency and reliability and easy access for the inspection, cleaning and repair of parts; the provision of an improved construction of valve, valveseat, and diaphragm-disk, designed to obviate variations in the freedom and extent of valve movement which result from dampness and other atmospheric changes in the present known constructions of said parts; and, generally, the provision of a simpler, more durable and more efficient pneumatic player action than has heretofore been produced.

The present application consitutes a division of an application filed by me on the 30th day of December, 1912, Serial No. 739,227.

My invention, its structural features, mode of operation, and advantages will be readily ascertained from the following detail de-- scription, when considered in connection with the accompanying drawings, in which I have illustrated one practical form in which the several features of improvement contemplated by my invention may be embodied, and in which Figure 1 is a vertical sectional view through a tier of superposed, wind-chests, with the lower valve-chest and power pneumatic shown in central longitudinal section, and the upper valve-chest and power pneumatic appearing in side elevation. 2 is a top plan view of the upper or stationary section of the pneumatic, showing also an improved packing for the joint between said pneumatic section and the superposed removable valve-chest. Fig. 3 is a bottom plan View of the removable valve-chest. Figs. 4c, 5 and 6 are enlarged detail views in vertical section of the lower valve-seat, the valve, and the diaphragm-disk, respectively; more particularly illustrating the novel structure of said parts whereby I eliminate the usual effects of swelling and shrinking upon the action of said parts, and insure a uniform behavior of said parts in action.

Referring to the drawing, 10 designates the usual vertical wind-trunk to which the main exhaust bellows of the instrument are connected, tapping one side of which trunk are a series of parallel superposed windchests, two of which are herein shown. As these wind-chests and the several actions connected thereto and served thereby are all duplicates, a description of one will suflice. The wind-chests comprise a main body portion formed of a channeled wooden strip 11, the upper and lower surfaces of which are covered with a thin veneer 12 of vulcanized fiber, and a fiat top or cover-plate glued thereto and comprising a thin wooden sheet 13 with a thin vulcanized fiber 14: on both sides thereof. Between the channel of the strip 11 and the cap or cover is formed the wind-space 15.

Attached to the under side of the windchest by screws 16 is the upper or stationary section 17 of the power pneumatic, the lower hinged section being indicated at 18, and the foldable bellows sides at 19. Attached to the free end of the hinged section 18 is the usual lifter-arm 20 which, either directly, or through the lifter 21, actuates the piano action.

22 designates each of the tracker-tubes, the lower ends of which latter connect with the individual player action units. As shown in Fig. 1, the lower end of the tube 22 registers with a duct 23 formed through the rear wall of the wind-chest.

The upper or stationary pneumatic section 17 is provided with the usual diaphragm-chamber and passages and ports communicating therewith and with the interior of the pneumatic, wind-chest and tracker-tube. In view of the fact, however, that this member, together with the cooperating valve-chest herein described, and the valve, valve-seats and diaphragm-disk, are

made of a molded substantially non-shrinkable composition material, such as is commonly employed for mouth-pieces and re ceivers of telephones, the forms of the several ducts are such as to permit the use of readily removable cores in the molding opration, and the open sides or ends of such ducts are sealed by an air-tight external covering, as hereinafter described.

25 designates the lower portion of the diaphragm-chamber, and 26 the central longitudinal duct connecting said diaphragmchamber with the lower end of the duct 23 through a short vertical duct 27, said duct 26, for convenience in molding, being extended through the end of the pneumatic section, as shown. On opposite sides of and parallel with the duct 26 are shorter ducts 29 formed by coring horizontal grooves in the opposite sides of the pneumatic section 17. The ducts 29 communicate at one end with the chamber 15 of the wind-chest through ports 30 (Fig. 2) and short ducts 31. in the bottom wall of the wind-chest; and the opposite ends of said duct 29 communicate through ports 32 with the diaphragm-chamber above the diaphragm, as clearly indicated in Fig. 1. In the forward end of the pneumatic section 17 is a duct 33, the lower end of which communicates freely with the interior of the pneumatic, while its upper end forms a port 34 (Fig. 2) that registers with a corresponding port in the valve-chest hereinafter referred to.

The sides and ends of the stationary pneumatic section 17 last described are covered with an air-tight bellows cloth 35, which may also conveniently be extended to form the bellows sides 19 of the pneumatic. This material seals the outer sides of the ducts 29, as well as seals the outer end of the duct 26. In the diaphragm-chamber 25 is mounted a diaphragm 36, centrally of which latter is secured a diaphragm-disk 37 through which the vibrations of the diaphragm are transmitted to the stem of the superposed valve. In the upper pneumatic section 17 is also formed the lower portion 28 of the bleed-duct or tracker-tube vent, the outer end of which is carried upwardly through the face of the pneumatic and is preferably covered by a screen 28'. For convenience in casting as well as for cleaning, the horizontal portion of the duct 28 is extended forwardly through the end of the pneumatic section 17 and is closed by a removable threaded plug 38.

Fitted to the upper face of the forward portion of the stationary pneumatic 17 is the removable valvechest 39. This valvechest is an integral structure of the same molded composition material as the pneumatic section 17, suitably cored to afford the requisite chambers and passages for cooperation with the upper pneumatic section.

In the lower face of the valve-chest is formed the upper section 40 of the diaphragm-chamber; and directly above the same is the valve-chamber 41. Extending forwardly of the valve-chamber 4-1 is a horizontal duct 42 that, for convenience in nnolding, is carried through the forward end of the valve-chest, but is closed at said forward end by a plug 43. Communicating with the duct 42 is a short vertical duct 44 that registers with the duct 33 of the upper pneumatic section through the port 34 of the latter. Between the upper portion 40 of the diaphragm-chamber and the lower end of the valve-chamber 41 is the lower valve-seat 45, through which plays the stem of the valve 46; the lower end of said valve-stem normally overlying the diaphragm-disk 37, and the valve itself normally resting upon the valve-seat 45. Integral with the top wall of the valve-chest directly above the valvechamber is a downwardly-turned annular flange 39 which constitutes the upper valveseat.

Referring to Figs. 4, 5 and G for a specific disclosure of an important novel structural feature that is common to all of said parts, and that constitutes an important part of the present invention, in the upper face of the lower valve-seat 45 is an annular groove 47 in which is fitted a packingring 48 of felt or like material, the upper face of which lies very slightly above the upper surface of the valve-seat; and over this packing-ring 4-8 is a covering 4-9 con sisting of a thin sheet of rubber or other moisture-proof material. This covering sheet is cemented to the upper side of the valveseat on both the inner and outer sides of the packing-ring 48, but is not cemented to the latter. In the valve 46 is a similar annular groove 50 containing a packingring 51 of felt or like material, the upper face of which, and the upper surface of the valve, are covered by a similar thin sheet 52 of rubber or like moisture-proof material, similarly applied. In the diaphragm-(iisk 37 is formed a central shallow socket containing a disk 54 of felt, or the like; and over the upper face of the felt disk 54 and the diaphragm-disk 37 is a covering 55 also of sheet rubber or like moisture-proof material, similarly applied. The felt packing of the lower valve-seat 45 cooperates with the under side of the valve 46; the felt packing of the valve 46 cooperates with the upper valve-seat 3i and the felt packing of the diaphragn'i-disk 37 cooperates with the lower end of the stern of the valve 46, said valve-stem having the form of a cross in transverse section to afford a relatively wide guide to the valve and also permit the free flow of air around the valve-stem when the valve opens.

I am aware that it has heretofore been known to apply to the upper surface of a diaphragm valve or valve-seat a sheet or strip of felt, and cement a sheet or strip of rubber to the upper surface of said felt sheet or strip. The cementing of the rubber to the felt, however, reduces and practically destroys the yieldable and self-adapting character of the felt; and by my construction I provide a perfect seal against the ingress of moisture without cementing the sealing material to the felt itself. In the valvechest is also formed the upper portion 58 of the bleed-duct, the inner end of which communicates with the upper portion 40 of the diaphragm-chamber above the diaphragm, while its outer end is turned downwardly at a right-angle through the lower face of the valve-chest and registers with the screencovered upper end of the duct 28 in the upper pneumatic section. Controlling the duct 58 is a bleed-valve 60 having a threaded shank 61. adapted to screw into the forward face of the valve-chest and a square inner end adapted to obstruct the bleed-duct at the bend or angle thereof to a degree that can be nicely regulated by its screw-threaded shank.

Between the upper face of the stationary pneumatic section 17 and the lower face of the valve-chest 39 is an interposed gasket or packing strip 57 of rubber that is suitably cut out to surround the upper diaphragmchamber 40 and the ports 32 as well as the registering ports of the ducts 33 and 44 and the bleed-vent ducts 2S and 58. This gasket is preferably cemented on its lower side to the upper face of the pneumatic section 17 as shown in Fig. 2; and is provided with raised ribs 62 that are stamped or struck up on the upper side of the gasket around the openings for the diaphragm-chamber, main exhaust duct, and bleed-duct, respectively. l/Vhen the valve-chest is inserted in place and clamped down upon the gasket, the raised ribs 62 are forced downwardly and thereby create air-tight joints around and effectively separate the diaphragmchamber and exhaust and bleed-ducts, so that conditions existing in any one in no wise affect the conditions existing in the others. The forward ends of the upper pneumatic sections are conveniently sup.- ported from spaced overhanging projections 64- of the wind-chest by means of wire hangers 65 passed through said projections 64 and at their lower ends entered into the ends of the pneumatic section 17.

The valve-chest, constructed and equipped as described, and forming the upper half of what I style a semi-unit system, is readily removable and insertible relatively to the upper pneumatic section 17, forming the lower half thereof, and when in place is confined laterally between the projections 64 of the wind-chest. The valve-chest is securely held in operative position by a U-shaped spring clamp 68, the cross member of which overlies the top of the valve-chest, and the side arms of which are suitably crimped so as to be compressed between the under sides of the overhanging projections 6i and longitudinal ledges 69 formed on the sides of each valve-chest, when the clamp is forced into place. To further facilitate the application and removal of the valve-chest, the sides of the latter are preferably corrugated, as shown at 70. By simply withdrawing the spring 68 and grasping the valve-chest by its corrugated sides, said valve-chest can be instantly withdrawn for examination and cleaning, when necessary, of the most vital parts of the structure, such as the valve,

vvalve-seat, diaphragm-disk, and wind and bleed-ducts and ports.

By making the valve-chest, upper pneumatic section, valve, valve-seat, and diaphragm-disk of a material that is substantially unafi'ected by atmospheric changes either of humidity or temperature, I provide a structure which is uniform and reliable in its operation; and by giving to the valve-chest the removable character described, I provide a simple means for obtaining ready access to the illterior parts of the action for cleaning, repair and renewal, when necessary, without requiring dismantling of the entire pneumatic action.

Minor changes may obviously be made in the details of structure within the purview and spirit of the appended claims.

I claim 1. In a pneumatic player action, the combination of a valve member provided with an annular face, a member provided with an annular seat for said valve, a ring of felt seated in the face of one of said members and adapted to be compressed by the seating of the valve, and a sheet of rubber overlying said ring and cemented to said member on the inside and the outside of said ring, said rubber sheet forming one of the working faces of said valve mechanism.

2. In a pneumatic player action, the combination of a valve member provided with a substantially flat annular face and a mem- I r ber provided with a substantially flat annular seat for said valve, one of said members being provided with an annular groove in its seat or face, a ring of felt seated in said groove and projecting slightly therefrom and adapted to be compressed by the seating of the valve, and a sheet of rubber overlying said ring and cemented to said member along annular zones on the inside and the outside of said ring, said rubber sheet forming one of the working faces of said valve mechanism.

3. In a pneumatic player action, the combination of an annular valve seat member, said member being provided with a central aperture to admit valve-guiding means, the face of said seat being provided with an annular groove surrounding but spaced apart from said aperture, a ring of felt seated in said groove and projecting slightly therefrom, a sheet of rubber cemented to said seat on either side of said ring, and a valve member having an annular face adapted to engage and compress said ring and provided with a projecting central portion adapted to be guided in said aperture, said rubber sheet forming one of the working faces of said valve mechanism.

4;. In a pneumatic player action, the combination of a chamber provided in its upper valve mechanism.

EMORY C. HISCOCK. Witnesses:

S. N. POND, E. G. INGERSOLL.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. C.

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